Instead of buying a policy through a travel agent or booking site, go to an online broker such as , which sells coverage from 21 carriers, including CSA Travel Protection, MedJet Assist, and Travelex. Before you buy, talk to a sales rep at the insurer, get a sample copy of the policy, ask if your specific concerns are covered, and make the agent point to the words in the fine print that prove coverage. For medical policies, be sure to ask about coverage for pre-existing conditions.